Topamax Clinical Pharmacology

HealthCentral.com

Drug Library
Topamax - Clinical Pharmacology [Topiramate]

Clearance of topiramate in adults was not affected by gender or race.
Pediatric Pharmacokinetics: Pharmacokinetics of topiramate were evaluated in patients ages 4 to 17 years receiving one or two other antiepileptic drugs. Pharmacokinetic profiles were obtained after one week at doses of 1, 3, and 9 mg/ kg/ day. Clearance was independent of dose.

Pediatric patients have a 50% higher clearance and consequently shorter elimination half-life than adults. Consequently, the plasma concen-tration for the same mg/ kg dose may be lower in pediatric patients compared to adults. As in adults, hepatic enzyme-inducing antiepileptic drugs decrease the steady state plasma concentrations of topiramate.

CLINICAL STUDIES

The results of controlled clinical trials established the efficacy of TOPAMAX Ž (topiramate) Tablets and TOPAMAX Ž (topiramate capsules) Sprinkle Capsules as adjunctive therapy in adults and pediatric patients ages 2-16 years with partial onset seizures or primary generalized tonic-clonic seizures, and in patients 2 years of age and older with seizures associated with Lennox-Gastaut syndrome.

The studies described in the following sections were conducted using TOPAMAX Ž (topiramate) Tablets.

Controlled Trials in Patients With Partial Onset Seizures Adults With Partial Onset Seizures

The effectiveness of topiramate as an adjunctive treatment for adults with partial onset seizures was established in six multicenter, random-ized, double-blind, placebo-controlled trials, two comparing several dosages of topiramate and placebo and four comparing a single dosage with placebo, in patients with a history of partial onset seizures, with or without secondarily generalized seizures. Patients in these studies were permitted a maximum of two antiepileptic drugs (AEDs) in addition to TOPAMAX Ž Tablets or placebo. In each study, patients were stabilized on optimum dosages of their concomitant AEDs during the baseline phase lasting between 4 and 12 weeks.